تفاعل #65394

معادلة التفاعل

6-cyano-3,4-dihydro-2,2-dimethyl-2H-1,4-benzoxazine

cyclohexane-1,2-dione

p-toluenesulfonic acid

→

6-cyano-3,4-dihydro-2,2-dimethyl-4-(6-oxo-1-cyclohexen-1-yl)-2H-1,4-benzoxazine

المردود 66.7%

المذيبات

toluene

ظروف التفاعل

المعالجة

1. 1
   درجة الحرارةthe solution was refluxed
2. 2
   درجة الحرارةunder heating for 4 hours
3. 3
   درجة الحرارةAfter cooling
4. 4
   غسيلthe reaction mixture was washed with saturated aqueous sodium hydrogen carbonate solution and aqueous sodium chloride solution
5. 5
   تجفيفdried over anhydrous magnesium sulfate
6. 6
   workup.DISTILLATIONthe solvent was distilled off under reduced pressure
7. 7
   أخرىThe residue was purified by silica gel column chromatography
8. 8
   غسيلthe resulting crude crystals were washed with ethanol

الإجراء التجريبي

In 15 ml of toluene were dissolved 0.5 g of 6-cyano-3,4-dihydro-2,2-dimethyl-2H-1,4-benzoxazine, 0.33 g of cyclohexane-1,2-dione and a catalytic amount of p-toluenesulfonic acid and using a Dean-Stark trap, the solution was refluxed under heating for 4 hours. After cooling, the reaction mixture was washed with saturated aqueous sodium hydrogen carbonate solution and aqueous sodium chloride solution and dried over anhydrous magnesium sulfate and the solvent was distilled off under reduced pressure. The residue was purified by silica gel column chromatography and the resulting crude crystals were washed with ethanol to give 0.5 g of 6-cyano-3,4-dihydro-2,2-dimethyl-4-(6-oxo-1-cyclohexen-1-yl)-2H-1,4-benzoxazine.

المصدر